Performance Assessment and Improvement of Two‐Phase Immersion Cooling for Multi‐Chip Module

ABSTRACT Thermal management of chips is a key bottleneck to power densification. Two‐phase immersion methods provide a potential alternative to realize the goal of thermal management on chips. In this paper, a numerical model of a multi‐chip module is established to evaluate the thermal performance of two‐phase immersion cooling based on the CFD method. The effects of coolant type, inlet velocity, and subcooling are investigated. The results indicate that the coolant type, inlet velocity, and subcooling significantly affect the temperature of the multi‐chip module. Compared with FC‐72, the chip temperature dropped considerably by using Novec 7100, which has higher latent heat. When the inlet subcooling remains constant, the chip temperature gradually decreases as the coolant flow rate increases. The chip temperature remains virtually stable when the inlet velocity exceeds 0.8 m/s. For this model, the optimal subcooling should be around 30°C. The baffle can effectively improve the overall temperature uniformity of the multi‐chip module. The addition of the baffle can reduce the temperature uniformity coefficient of the chip by up to 63.08%. After further optimization, the temperature uniformity is increased by 35.89%.